Re: can we mark upper/lower/textlike functions leakproof?

On Wed, Jul 31, 2024 at 2:43 PM Joe Conway <mail@joeconway.com> wrote:
> I still maintain that there is a whole host of users that would accept
> the risk of side channel attacks via existence of an error or not, if
> they could only be sure nothing sensitive leaks directly into the logs
> or to the clients. We should give them that choice.

I'm not sure what design you have in mind. A lot of possible designs
seem to end up like this:

1. You can't directly select the invisible value.

2. But you can write a plpgsql procedure that tries a bunch of things
in a loop and catches errors and uses which things error and which
things don't to figure out and return the invisible value.

And I would argue that's not really that useful. Especially if that
plpgsql procedure can extract the hidden values in like 1ms/row.

--
Robert Haas
EDB: http://www.enterprisedb.com